Prospecting (machines)

[WM6]

Nothing new about prospecting here, or I am blind?

Prospector are probably not ready to explain his experience with different type of machines? So no comparition test or reviews of prospecting PI and VLF machines.

I sympatize with beauty Whites TDI (jealous of Geo).

[grungymike]

not ready???

The reason I joined this forum was complete frustration with a White's GMT. I've been doing considerable reading about different types of machines, and am convinced the way to go is pulse induction. The thing is a machine like the GMT (an induction balance type) goes completely nuts in strongly mineralized ground or around hot rocks. Example- last time I took the GMT out, in 5 minutes I found 3 different rocks that not only gave a good clear signal, but even set off the iron ID.

Pulse induction machines are far less responsive to strong mineralization and can easily ignore hot rocks
with a little fine tuning of the 1st delay.

The down side is that no one has yet figured out a decent discrimination method for a PI machine that is effective,
or if they have, they're quietly running for the nearest patent office...

IB machines on the other hand have some very sophisticated discrimination formats.

Bear in mind that even the best discrimination method is not perfect. There's a well worn axiom amongst nugget hunters- when in doubt DIG!!! With that thought in mind, my opinion is that the advantages a PI offers in the form of ability to handle tough ground outweigh the lack of good discrimination.

Bottom line is (in my opinion) IB machines make better treasure and coin hunters, PI machines make better nugget shooters.

gm

[WM6]

The reason I joined this forum was complete frustration with a White's GMT. I've been doing considerable reading about different types of machines, and am convinced the way to go is pulse induction. The thing is a machine like the GMT (an induction balance type) goes completely nuts in strongly mineralized ground or around hot rocks. Example- last time I took the GMT out, in 5 minutes I found 3 different rocks that not only gave a good clear signal, but even set off the iron ID.

Bottom line is (in my opinion) IB machines make better treasure and coin hunters, PI machines make better nugget shooters.

gm

Hi grungymike,

I was thinking about White's GMT, but not decided to buy yet. As I understud some writings White's GMT is very suitable to detect very tinny nuggets, but not on all sort of terrains.

I am not prospecting yet (I live in geological inadequate area), but I am planning to do some trip in summer for prospecting. So all experiences with prospecting detectors and advices are interesting for me. I give my sympaties to White's TDI, but will not to buy it in first step. First some destination have to be checked on prospecting possibilities, then maybe ...

[grungymike]

PI vs IB

What you've heard about the GMT matches my experience with it. I'ts a damned good machine, I've found 4 grain flakes with it, but it's so sensitive it's kinda like trying to walk a tightrope in a hurricane. The areas I hunt in I have to slam the SAT down to almost nothing and back way down on the gain to get a stable threshold.

Everything I've read indicates this is true for all of the
induction balance (VLF) machines. Their strong point is strong discrimination ability, but they're real sensitive to variations in the background mineralization.

A pulse induction machine works on a completely different principle, making it much less sensitive to anomalies in the ground signal. They still have their problems, that's why Minelab uses Double D coils on their gold hunting machines, but they can still function in an environment that would completely swamp an IB machine. That gives them a real advantage in most goldfields.

I was looking at buying a TDI, I'm nationalistic enough to prefer buying American, but the way the controls are designed is just weird to me. I think they're trying to design a do all machine but what I want is well built basics designed specifically for nugget shooting.

I was ready to give it up when I stumbled on this site.
Studying the Hammerhead circuit got me committed to the idea of building my own machine. I'ts been a steep learning curve for me, with 2 false starts, and more work ahead, but when I put my 1st unit into field tests, I'll have an intimate understanding of what the machine can (or is supposed to) and can't do, and why.

And that's enough philosophical babbling for one post...
later-
gm

[Tinkerer]

Discriminationg PI

The down side is that no one has yet figured out a decent discrimination method for a PI machine that is effective,
or if they have, they're quietly running for the nearest patent office...

Hi Grungymike,

have a look at the TINKERERS_V1 DISCRIMINATING PI at the post below.

It is an "OPEN SOURCE" project, free for anybody to try, copy, improve and even commercialize. No patent.

http://www.geotech1.com/forums/showp...63&postcount=1

Tinkerer

[WM6]

The down side is that no one has yet figured out a decent discrimination method for a PI machine that is effective,
or if they have, they're quietly running for the nearest patent office...

Hi Grungymike,

have a look at the TINKERERS_V1 DISCRIMINATING PI at the post below.

It is an "OPEN SOURCE" project, free for anybody to try, copy, improve and even commercialize. No patent.

http://www.geotech1.com/forums/showp...63&postcount=1

Tinkerer

Hi Tinkerer,

I highly appreciate your work on "tinkerer PI" projects, but there are too many threads inside your projects and partially uncler circuit for most of us, to be able to put all this circuit puzzle togheter.

Maybe you can make some résumé and put all parts togheter in one finaly thread? Thank you!

Example:

[WM6]

I was looking at buying a TDI, I'm nationalistic enough to prefer buying American, but the way the controls are designed is just weird to me. I think they're trying to design a do all machine but what I want is well built basics designed specifically for nugget shooting.

You mean so? There are some posts on different forums which explan that it is not to complicated to use TDI on proper way. I never seen TDI and havent any experience about its controls but some explanation I find acceptable.

[Tinkerer]

Hi Tinkerer,

I highly appreciate your work on "tinkerer PI" projects, but there are too many threads inside your projects and partially uncler circuit for most of us, to be able to put all this circuit puzzle togheter.

Maybe you can make some résumé and put all parts togheter in one finaly thread? Thank you!

Example:

WM6,

thanks for the feedback.

You are absolutely right. I need to clean up and post the final version.

Tinkerer